Exhaust hood



R. P. ALLEN, JR., E-r ALI 2,516,840

. EXHAUST HOOD Aug. 1, 1950 3 Sheets-Sheet, 1

Filed March 26, 1948 INVENTORS R. R ALLEMJR.

w H. somv ATi'ORA/EV 1950 R. P. ALLEN, JR., ET AL 2,516,840

EXHAUST noon Filed March 26, 1948 3 Sheets-Sheet 2 r INVENTORS R. R ALLEN JR.

WH SCH/V FIG. 2

AT'II'ORNEV Aug. 1, 1950 R. P. ALLEN, JR., El AL 2,516,340

EXHAUST HOOD 3 Sheets-Sheet 3 Filed March 26, 1948 m/vawroks .RF. ALLEN-JR wHj OHN ATTORNEY latentecl Aug. 1, 1 950 7 2,516,840 EXHAUST'HOOD Raymond P. Allen, Jr., and William H. Sohn, Baltimore, Md., assignors to..Western Electric Company, Iiworporated,.New

poration of New York I Application March 26, 1948, Serial No. 17,195

9Clairns. (ciao-41) This invention relates to exhaust hoods, and more particularly to exhaust hoods for catching and carrying away chips from cutting machines.

In the use of cutting machines to cut away portions of articles, the chips which are formed must be cleaned away from the machine. Exhaust hoods have been proposed for carrying away chips from cutting machines, but in machines where the work must be moved from positions outside exhaust hoods into engagement with the cutting tools of the machines, the exhaust hoods cannot completely enclose the cutting tools. Hence, the hoods known in the past have been ineffectual to prevent the escape of considerable portions of the chips to the area around the machine.

An object of the invention is to provide new and improved exhaust hools.

Another object of the invention is to provide new and improved exhaust hoods for catching and carrying away chips from cutting machines.

A further object of the invention is to'provide new and improved exhaust hoods for substantially completely enclosing cutters during the operations of the cutters on workpieces and to permit the workpieces to be moved from positions outside the hoods into engagement with the cutters.

An exhaust hood illustrating certain features of the invention may include a nozzle positioned near a cutter and provided with an opening therein to permit a work carriage to be moved into operative relationship with a cutter, means for creating a stream of air having a high velocity through the nozzle to carry chips therethrough, and a covering carried by the carriage for closing the opening of the nozzle and fitting telescopically with respect to the nozzle to permit the carriage to be moved toward and away from the cutter.

A complete understanding of the invention may be obtained from the following detailed description of exhaust hoods forming specific embodiments thereof, when read in conjunction with the appended drawings, in which:

Fig. 1 is a vertical section of an apparatus including an exhaust hood forming one embodiment thereof;

Fig. 2 is a front elevation of the apparatus shown in Fig. 1;

Fig. 3 is a fragmentary, plan view of the apparatus shown in Fig. 1;

Fig. 4 is a front elevation of an apparatus including an exhaust hood forming an alternative embodiment of the invention, and

York, N. Y., a cor- Fig. 5 is an enlarged, vertical section taken along line 5-5 of Fig. 4.

Referring now in detail to the drawings, a bracket l0 securesa hood 12 to an overarm M of a milling machine, which includes a cutting spindle 16 having a cutter 18 mounted thereon, which rotates in a clockwise direction, as vie-wed in Fig. l. A work carriage 20 may be slid from the left, as viewed in Fig. 1, to move work 22 through an opening 24 in the hood [2 into engagement with the'cutter I8, which cuts chips from the work and throws them toward a tapered portion 26 of the hood l2.

The hood [2 has an opening 28 at the bottom portion thereof to permit the carriage to be moved into working relationship with respect to the cutter l8, and to prevent chips from falling through the opening 28, a pan 30 secured to the carriage fits telescopically into the lower portion of the hood and covers the opening 23 at all times that the cutter I8 is in engagement with the work.

A duct 32connected to a restricted portion 3 of the tapered portion 26 is connected to a header 36 in which the pressure is substantially less than that of the atmosphere. The low pressure in the header 36 causes air to be drawn through the hood l2 and through the duct 32 at a very high velocity so that the chips, which are thrown toward the small end of the tapered portion 25 of the hood l2, are carried into the header from the hood I 2. Part of the chips are carried by the air stream directly into the header and part fall on the pan 3% and the carriage. The chips falling on the pan and the carriage arepicked up by the air stream travelling at a high velocity near the restricted portion of the hood as the pan is moved toward the small end of the tapered portion of the hood. Since the tapered portion 26 Of the hood I2 is mounted in facing relationship with respect to the chips from the work 22 as the chips are thrown by the cutter, a guard portion 31 ofthe hood I2 enclosing the cutter [8 may be verylarge. That is, the chips thrown by the cutter is are carried by the pan and the carriage sufficiently far into the tapered portion 28 of the hood I2 to permit the stream of air flowing in the portion of the hood l2 adjacent to the cutter 18 to travel at a relatively low velocity, and the velocity of the air stream in the portion of the hood 12 over the pan 30 is high so that the chips are picked up and carried into the header.

The hood I2 is provided with a large opening 40 at an end of the spindle I6 so that after a plate 42 normally secured to the hood l2 over the open-.

ing 40 by wing nuts 44-44 is removed from the hood, the spindle 16 may be detached from the machine and withdrawn with the cutter thereon for sharpening the cutter or other maintenance operations without dismantling the hood from the machine. The portion of the hood immediately adjacent to the cutter [B is substantially larger than the cutter 18. Hence, removal of the spindle of the machine is facilitated, and due to the position of the hood with respect to the cutter, the exhaust function of the hood is not impaired by this large clearance.

A bracket 50 (Fig. 2) is secured adjustably-to the bracket 10 by cap screws -5252, whichproject through slots 5454 formed in the bracket 50. A front cover 56 similarly is secured to the bracket 50 to increase the range of adjustment of the front cover with respect to the bracket 10 so that the cover 56 may always be positioned close to the top of the work throughout a wide variation in the height of work to be milled. The cover 50 increases the velocity of the air stream over the carriage, and acts-as a.-guard against injury from contact with the cutter [8.

Certain features of the exhaust hood 12 are disclosed and claimed in copending application Serial No. 17,194, filed March'2'6,l948,by R. P. Allen, Jr., F. -D. Johnston and W. H. Sohn for Exhaust Hoods.

An exhaust hook (Figs. 4 alternative embodiment of the invention-includes a pair of suction nozzles llZ-HZ, which are mounted at edges of duplex cutters lIB-l l8 and create air streams of high velocities across the faces of the cutters. In order to position the nozzles HZ-HZ close to the-cutters ll8-|l8 and still provide clearancefor a work carriage I20 and work I22 as the carriage moves work I22 into engagement with the lower portions ofthe cutters, the nozzles are provided with L-shaped cutout portions l23l23. Generally L-shaped closure plates l3tl30 carried by the carriage fit telescopically with respect to the housings lI2-| [2 to completely close the cutout portions at all times while the work is in engagement with the cutters llS-i l8. The telescopic closure plates serve to deflect chips thrown-thereagainst by'the cutters back toward the nozzles lI2-l l2, and also create high velocity air streams drawn to the nozzles 1 l2! 12 past the faces of the cutters. Guards isl ll cover the upper portions of the cutters and cause the air being drawn into the nozzles to flow primarily'across the ends of the work. The closure plates ltlJ-lttifit around the nozzles, and carry the chips thereto.

The above-described exhaust hoods serve to remove chips formed by the cutters l8 and l l 8 H8 much more effectively than do exhaust hoods hitherto known, and facilitate maintenance of the cutting machines with which theyare' associated. They maintain high 'air"velocity air streams at the critical points and substantially cover the cuttin elementsthroughout thecutting operations without interfering with the feed of work to the cutting elements.

What is claimed is:

1. An exhaust hood for a machine having a rotary cutter and a work carriage, which comprises a nozzle positioned near the cutter and provided with an opening in a wall thereof to permit the work carriage to be moved into operative relationship with the cutter and past the cutter, means for creating a high velocity air stream-through the nozzle to carry chips therethrough and r covering carried and forming an 1 '4 by the carriage for closing said opening of the nozzle and fitting telescopically with respect to the nozzle to permit the carriage to be moved toward and away from the cutter.

2. An exhaust hood for a machine having a cutter and a work carriage, which comprises a nozzle positioned on the recess side of and near the cutter'and'provided with'an opening in the side wall thereof to permit the work carriage to be moved into operative relationship with the cutter and past the cutter, means for creating a-high velocity air stream through the nozzle to carry chips therethrough, and a covering carried by the carriage for closing the open por- -tion of the nozzle and fitting telescopically with respect to the nozzle to permit the carriage to be moved toward and away from the cutter.

'3. An exhaust hood for a machine having a cutter and a Work carriage, which comprises an exhaust housing positioned partially over the cutter andprovided with an opening therein to permit the work; carriage to be moved into operative relationship with and past the cutter, means -forcreating high velocity air stream through the suction nozzle mounted at the side of the cutting tool opposite that toward which work is moved and adjacent to the cutting tool and being provided with a slot in the wall thereof forproviding clearancefor'the carriage and work as the carriage moves work past the cutter toward the nozvz-le,-and a cover mounted on the carriage and fitting the nozzle telescopically for covering the slot.

5. An exhaust hood for a machine including acutting tool and a carriage-formoving work into engagement with and past the tool, which comprises a housing, a portion of the housing fitting partially over the cuttingtool for providing clearance for the-carriage asthe carriage moves work past the cutter, the remainder of the housing mounted on the carriage and fitting the firstmentioned portion of the housing telescopically.

6. An exhaust'hood for removingchips from a machine having :a rotary working tool and a reciprocatory work carriage, which comprises a housing closely surrounding the tool-and having an opening in the bottom-thereof topermit the reciprocatory work carriage toadvance into and out of operative relationship with respect to the tool, a floor mounted on the carriage for closing the opening beneath the tool.

7. An exhaust hood for removing chips -from a machine having a rotary working tool *and a reciprocatory work carriage, which comprises a housing "closely surrounding the tool and having arr-opening in the bottom thereof-to permit the reciprocatory workcarriage to advance into-and out of operativereationship'with respect to't'he tool, a floor fitting telescopically into the housing and mounted on the carriage, said floor-constantly closing the opening beneath the tool.

8. In an apparatus including -a cutter and a carriage for moving workin -a predetermined 'direction into engagement withand' past thecutter, an improved exhaust ho0d," which comprises a suction nozzle hav'ing 1 an opening in the 'side wall thereof mounted at' the side of thecutter opposite to that toward which the work is moved and in a position pointed in a direction opposite to said direction of movement of the carriage, said opening in the nozzle serving to provide clearance for the carriage and the work as the work is moved past the cutter, and a cover carried by the carriage and fitting the nozzle telescopically to cover the portion of the opening not occupied by the carriage and the work. I v

9. In an apparatus including an end cutter and a carriage for moving work in a. predetermined direction into engagement with and past the cut.- ter, an improved exhaust hood, which comprises a suction nozzle generally rectangular and having L-shaped openings in adjacent walls thereof mounted at the side of the cutter opposite to that toward the work is moved and in a position pointed in a direction opposite to said direction of movement of the carriage, said opening in the nozzle serving to provide clearance for the carrlage and the work as the work is moved past REFERENCES CITED The following references are of record in the tile of this patent:

UNITED STATES PATENTS Number Name Date 108,822 Pitkin et a1 Nov. 1, 1870 789,741 Kaltenbach May 16, 1905 2,345,958 Woodbury Apr. 4, 1944 Certificate of Correction Patent No. 2,516,840 August 1, 1950 RAYMOND P. ALLEN, JR, ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 1, line 18, for hools read hoods; column 3, line 30, for the Word hook read hood; column 5, line 17 after toward insert which;

and that the said Letters Patent should be read as corrected above, so that the same may conform to the record of the case in the Patent Office. Signed and sealed this 13th day oi February, A. D. 1951.

THOMAS F. MURPHY,

Assistant Commissioner of Patents. 

